Most brushless synchronous machines include two separate machines, the main machine and the exciter machine. The exciter machine provides excitation power to the field windings of the main machine. The stator of the exciter has electromagnet poles that are provided with power from a separate power stage in an automatic voltage regulator (“AVR”). By regulation of one or both of the voltage and frequency of the excitation on the stator of the exciter machine, the excitation of the main machine can be indirectly regulated. Such a power stage providing power to the excitation machine requires components such as transformers, breakers and active power electronics. In addition to the components required for the power stage, the exciter of a 20MVA class machine weighs about 2% of the total weight of the combined main machine and exciter machine, and can take up to 20% of the total length of the shaft of the combined machines. Thus, the total weight and size of the combined machines is greater than would otherwise be without an exciter and associated equipment required to operate the exciter. A longer shaft also reduces the critical speed of the rotor. Thus, it would be beneficial to be able to provide excitation to the main machine without the necessity of an exciter machine and associated power stage.